This 1999 photo shows the Bayonne Bridge (NY 440-NJ 440) over the Kill van Kull, as shown from the Mariners Harbor section of Staten Island. (Photo by Steve Anderson.)

CROSSING THE KILL VAN KULL: Running between the southern tip of the Bayonne Peninsula and the north shore of Staten Island, the Kill van Kull joins New York Harbor with Newark Bay. Named after early Dutch settlers in the area, the waterway is among the busiest shipping channels in the world. Soon after commercial ferry service was initiated in the 1820's, towns grew on either side of the channel, developing a system of streets, rail lines and transportation terminals as extensions of the ferry.

In the early years of the twentieth century, pressure grew inevitably for a bridge linking Staten Island with the Bayonne Peninsula. Planners expected that the bridge would follow the route of the ferry, since the construction of the bridge and its approaches would involve the least amount of destruction to taxable property, and would be most convenient to major street connections on both sides of the Kill van Kull.

Soon after the governors of New York and New Jersey authorized the Port of New York Authority in 1921, the new agency approved the Bayonne Bridge for construction. The Port Authority, whose jurisdiction was limited to interstate transportation, expected that the Bayonne Bridge would provide a convenient route between Staten Island and the Holland Tunnel.

Before ground was broken for the Bayonne Bridge, engineers considered the following designs suitable for a main span of 1,500 feet, including designs for a cantilever bridge and a suspension bridge:

Almost immediately, the cantilever design was deemed too impractical, too unattractive, and because it required the most amount of steel, too expensive.

The suspension bridge design, which included deck stiffening trusses and diagonal tower bracing, was seriously considered until it was discovered that deep, expensive excavations in the bedrock for the anchorages would be needed. Moreover, the accommodation of two proposed rail lines added to the cost.

The steel-arch design planned by Othmar Ammann, the master bridge designer and chief engineer of the Port Authority, was ultimately considered most practical for this route. Although the cost of the suspension span was estimated at one-half million dollars less than that of the arch span, the greater stiffness of the arch design was deemed suitable to carry the proposed rail lines.

The revised design of the Bayonne Bridge arch was to feature a slender, hyperbolic curve over the roadway, while the stiffening trusses were to form repetitive triangles. Building upon the design of the Hell Gate Bridge, which was constructed by Ammann's mentor, Gustav Lindenthal, the steel-arch design of the Bayonne Bridge was to blend in with the low-lying industrial landscape. Architect Cass Gilbert, who joined Ammann in the design work for the George Washington Bridge, assisted in the final design work.

This 1930 photo shows the construction of the suspended roadway on the Bayonne Bridge. The roadway is suspended by wire rope hangers. (Photo by Port Authority of New York and New Jersey.)

DESIGN AND CONSTRUCTION: Ground was broken for the Bayonne Bridge on September 1, 1928. The span is comprised of a two-hinged, spandrel-braced trussed arch in which the bottom chords form a perfect parabolic arch. As the span's primary structural members, these manganese-steel chords carry most of the dead load and uniform live load, which is then transferred to the concrete abutments. The span's top chords (which were constructed from a lighter silicon steel) and web members are stressed by live loads and temperature.

The arch trusses, which run parallel to the outside of the suspended roadway, are 67 feet, 6 inches deep at the abutments, but taper gradually toward midspan to a depth of 37 feet, 6 inches. At midspan, the chords rise 266 feet above Kill van Kull. According to Ammann:

The general outline of the arch, with height decreasing from the center toward the ends, was preserved principally for its pleasing appearance.The arch is comprised of 40 connected truss segments, each of them fabricated off-site. Unlike most free-standing arch bridges, which are constructed by scaffolding, the Bayonne Bridge was constructed by a combination of cantilever and falsework methods. To keep the Kill van Kull open at all times as an important naval and shipping route, only a few bents and a traveling crane were used to assemble the bridge.

The abutments were constructed to support the transfer of the bridge's load from the lower chords. Solid rock from the New Jersey Palisades continues along the Bayonne Peninsula, under the Kill van Kull and onto Staten Island, making for an ideal foundation. Originally designed for encasement in ornamental stonework, the abutments were left with their steelwork exposed due to the fiscal restraints of the Great Depression. (Another Port Authority crossing, the George Washington Bridge, did not have granite facing as originally planned. In both cases, the lack of granite facing arguably adds to the purity of the steel structure.)

Once the arches were connected, work commenced on constructing the bridge's roadway and approaches. A network of perpendicular beams, girders and stringers support the bridge's suspended deck. Sections of the roadway deck, which could accommodate four lanes of vehicular traffic (with expansion room for two additional traffic lanes or light rail tracks), were fabricated off-site, transported by barge, and hoisted into place. A pedestrian walkway was cantilevered from the primary roadway deck.

In order to reach a midspan point of 150 feet over the Kill van Kull, long approaches rising with a four percent grade were constructed on either side of the main arch. Reinforced concrete piers, ranging in height from 20 feet to 110 feet, support a steel-plate and concrete roadway.

When the $13 million Bayonne Bridge opened on November 15, 1931, it had become the longest steel-arch bridge in the world, beating the Australia's Sydney Harbor Bridge (which also opened that year) by a mere two feet. From a view on the roadway, one can observe a network of steel lace in the 325-foot-high arch. These design attributes earned accolades from the American Institute of Steel Construction, which bestowed on the Bayonne Bridge the honor of "Most Beautiful Structure of Steel of 1931."

Since 1952, the Bayonne Bridge has carried the Route 440 designation between New York and New Jersey. The Bayonne Bridge maintained the title as the world's longest steel-arch span until 1978, when the New River Gorge Bridge, with its 1,700-foot center span, opened in Fayetteville, West Virginia. Even today, the Bayonne Bridge has the second-longest steel arch span in the world.

PLENTY OF CAPACITY LEFT: Traffic engineers had expected that an additional two lanes would be needed on the Bayonne Bridge by 1955. However, a significant commuting pattern between Staten Island and Manhattan via the Bayonne Bridge-Holland Tunnel route never materialized. Indeed, during its first 15 years, very few people used the Bayonne Bridge. In 1946, a devastating fire swept through the St. George Ferry Terminal on the northeast corner of Staten Island. Ferry patrons, many of whom did not even know about the existence of the Bayonne Bridge, began to use it (as well as the Holland Tunnel) as an alternate route to Manhattan.

THE BAYONNE BRIDGE TODAY: The Bayonne Bridge carries approximately 20,000 vehicles per day (AADT) over its four lanes. The bridge links the Dr. Martin Luther King, Jr. Expressway (NY 440) and the Staten Island Expressway (I-278) with NJ 440 in Hudson County, New Jersey. In addition, the Bayonne Bridge has a walkway for pedestrians and bicycles.

At the end of 2003, the Port Authority completed high-speed EZ-Pass lanes at the Bayonne Bridge toll plaza. The left Staten Island-bound toll lanes have a maximum speed of 25 MPH, versus the original EZ-Pass lane speed of 5 MPH. Because of the close proximity of the other toll lanes, it was not possible to build highway-speed EZ-Pass lanes at this location.

In 2004, the Port Authority completed a four-year, $46 million project to rehabilitate the main steel-arch span and the bridge deck.

TALLER SHIPS PROMPT CALLS TO REPLACE THE BRIDGE: When the Bayonne Bridge opened, it had ample clearance for the tallest freight vessels, which at the time measured 100 feet to the top of the mast. With the tallest vessels now measuring up to 175 feet high, many cargo ships traveling the Kill van Kull must pass under the bridge at low tide because there is not enough vertical clearance.

Fearful of losing port business to other East Coast ports, officials are considering either raising or replacing the Bayonne Bridge:

RAISING EXISTING SPAN: Under this scenario, the roadway would be removed and the bridge piers extended higher. Using the existing structural steel of the superstructure, new suspension cables would be installed to suspend a new four-lane roadway 185 feet above Kill van Kull, or 35 feet above the current position. Construction of this design, whose cost is estimated at approximately $500 million, has been criticized as marring the appearance of the original bridge.

BRIDGE REPLACEMENT: Under this scenario, a new bridge would be built alongside the original bridge. The new bridge, whose design has not been determined (though it likely would be a cable-stay design), would carry four lanes of vehicular traffic and possibly two tracks for a future Hudson-Bergen light rail extension to Staten Island. It also would have at least 200 feet of vertical clearance. The cost of this plan would be approximately $1 billion.

The Port Authority estimates that either plan would take at least three years to complete upon final approval by Federal and state governments. The agency also anticipates that Kill van Kull would have to be closed to navigation for one month under construction.

This 2001 photo shows the interior arches along the northbound Bayonne Bridge (NY 440-NJ 440). Note the lack of a median barrier on the four-lane arch span. (Photo by Mike Tantillo.)

Type of bridge:Construction started:Opened to traffic:Length of arch span:Length of New Jersey viaduct:Length of Staten Island viaduct:Total length of elevated structure:Width of bridge:Number of traffic lanes:Width of roadway:Channel clearance of bridge at mid-span:Height of arch above water at top:Number of truss segments:Width between arch trusses:Height between spandrel arches (at top):Height between spandrel arches (at bottom):Structural steel used on bridge and approaches:Cost of original structure:

SOURCES:The Bridges of New York by Sharon Reier, Quadrant Press (1977); Great American Bridges and Dams by Donald C. Jackson, Preservation Press-John Wiley and Sons (1988); Engineers of Dreams by Henry Petroski, Vintage Books-Random House (1995); "A Guide to Civil Engineering Projects in and Around New York City," American Society of Civil Engineers (1997); Bridges by Judith Dupre, Black Dog And Leventhal Publishers (1997); Perpetual Motion: The Illustrated History of the Port Authority of New York and New Jersey by Joe Mysak and Judith Schiffer, General Publishing Group (1997); The Creation of Bridges by David Bennett, Chartwell Books (1999); Six Bridges: The Legacy of Othmar H. Ammann by Darl Rastorfer, Yale University Press (2000); "Happy Birthday: EZ-Pass Turns Ten" by Sy Oshinsky and Chris King, AAA-Car and Travel Magazine (December 2003); "Cutting It Close: Bayonne Bridge's Height Is Trouble for Shops and a Costly Question for the Port Authority" by Susan Todd, The Star-Ledger (5/19/2006); New Jersey Department of Transportation; North Jersey Transportation Planning Authority; Port Authority of New York and New Jersey; Hank Eisenstein; Dave Frieder; Ralph Herman; Marc Rivlin; Christof Spieler; Stéphane Theroux.